99 Lives - At the Title screen, press Left, Right, Right, Right, Down, Up, Right, Up, A. 

Unlimited Health in Sparx Worlds - At the Title screen Press, Down Up Up Down Left Right Right Left A 

Unlimited Weapons in Sparx Worlds - At the Title screen Press, Down Right Up Left Left Up Right Down A 
Use commands during game play in Sparx worlds:

Invincibility shield: Press Up + Select.
Smart bomb: Press Right + Select.
Rapid fire: Press Left + Select.
Homing bombs: Press Down + Select.
All keys: Press L + Select 

The trick to getting the bells in the right order in market Mesha is to choose 1 letter to represent each bell. Then all you need is a pen and paper and write down the special letters each time when that guy shows you.

Quick glide stop - When gliding in the air after jumping, press A again to immediately stop and drop to the ground. 

Unlimited lives - Go to the House Of Winter Fairies and from the portal go down until you reach a jar with a life. Enter the portal to go to the house of Autumn Fairies. If you return to the Winter Fairies, you will find the jar again. Repeat the process to get unlimited lives.

Extra Sparx weapons - When Press Start appears at the title screen, press Right, Up, Right, Left, Down, Up, Left, Down, A. 

Use one of the following commands in Sparx worlds:
Invincibility shield: Press Up + Select
Smart bomb: Press Right + Select. 
Rapid fire: Press Left + Select. 
Homing bombs: Press Down + Select. 
All keys: Press L + Select 

Select level - Press Up, Up, Down, Down, Left, Right, Up, Down, A, at the title screen.
Level portals opened - When Press Start appears at the title screen, press Up, Up, Down, Down, Left, Right, Up, Down, A. 
Warp - Press Left, Right(2), Left, Up, Left(2), Right, A when "Press Start" appears at the title screen.
Warp unlock all levels - Press Down, Up, Down, Left, Right, Up, Left, Up, A when [Press Start] appears at the title screen.

Infinite Lives - Go to Winter Fairy Home and below the portal will be a jar. Break it open to get an extra life. Go into the portal to return to Autumn Fairy Home and go back into it again. Below the portal will be another jar. Keep on doing this until you are satisfied with the number of lives you have.

Get All Levels: - To open all level Portals - At the [Title Screen] when you see the flashing [Press Start] Press Up, Up, Down, Down, Left, Right, Up, Down, A.
Sent in by Mandy D

Games Shark Codes:

Must Be On [M] 6761F8B0A5366146   21703185C0A6EA4B
Infinite Lives A2D69805C8081253 
Infinite Health With this code, the little fly will be a yellow rectangle. 7D3B1F6811118B49 
Max Gems 19F923CE699A31C5 
Max Fairies CF22A1B8A7DAC26A 
Autumn Fairy Home Complete This code will make the portal to this world black. DEB02D9CB165046B
D5ED7EEC7CABCD3D   287E06586232DA2E

Market Mesa Complete This code will make the portal to this world black. F5B73AE40134DDA8
B4AD356EDBCCD6CD   3ECDBEBFB7A962A9

Lava Prairie Complete This code will make the portal to this world black. DC1CB7A0D36114FF
D18F8F1751D8B3C8   A8BFE8B7B85E03A8

Mermaid Coast Complete This code will make the portal to this world black. 62520AD7F963898A
2AD53D4010F24C2A   347FA3EC4A061540

Stone Age Speedway Complete This code will make the portal to this world black. A18D9D50ECEF8EF0
B6FAC85D82FE267C   7EFBDB2F05C3F66B

Ant Farm Complete This code will make the portal to this world black. 6C34315CA247A61B   52FF468D9665D393